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Zubareva O. N. Skripal'shchikova L. N. Greshilova N. V. Kharuk V. I. 《Russian Journal of Ecology》2003,34(6):375-380
In this study, we have analyzed the degradation of pretundra forests and distinguished the levels of pollution using ground-based and remote-sensing data. The study region is located in the area exposed to emissions from the Norilsk Mining and Smelting Works. The main components of emissions are sulfur dioxide, nitrogen oxide, and heavy metals. Currently, the zone of damaged forests extends for more than 200 km. The comparison of the zones of degradation of pretundra vegetation distinguished in satellite images with the results of ground-based observations yielded high similarity coefficients (0.73–0.83) of the Kappa statistics. The zones of vegetation state were classified by NDVI values. The images from the NOAA/AVHRR satellite may be used for delimiting the zones of vegetation degradation by the proposed method. 相似文献
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The influence of recreation activity on grass cover was studied in a herbaceous birch forest within a territory of city development. Effects of the activity depended on size and arrangement of recreation sites. It was found that most of the forest was at the second stage of degradation, while degradation of forest edges was considered as intermediate between the second and third stages. Forest edges and glade-clump communities play a particular role in maintaining the stability of recreational forests.These ecotones are both barriers preventing introduction of alien plant species into a cenosis and centers of dissemination of ruderal and meadow species. 相似文献
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